Question

Match List I with List II:
List I
A. Griseofulvin
B. Primarily bacteriostatic
C. Primarily bactericidal
D. Inhibit DNA gyrase
List II
I. Erythromycin
II. Penicillin cephalosporin
III. Ciprofloxacin
IV. Vancomycin
Choose the correct answer from the options given below:

• A. A-II, B-I, C-IV, D-III
• B. A-III, B-II, C-IV, D-I
• C. A-IV, B-III, C-II, D-I
• D. A-I, B-II, C-III, D-IV

Hint:

To solve this quickly, look for the most specific mechanism: DNA gyrase inhibition is the unique mechanism of fluoroquinolones like Ciprofloxacin (D-III). This immediately helps narrow down the correct option.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
Veterinary pharmacology requires a thorough understanding of antimicrobial classification, mechanisms of action, and their physiological effects on microbial structures.
Antimicrobials are grouped by their chemical class, source organism, mechanism of action (such as cell wall synthesis inhibition, protein synthesis inhibition, or nucleic acid synthesis inhibition), and their biological effect (bacteriostatic versus bactericidal).

Step 2: Detailed Explanation:
Let us match the items systematically:
1. Griseofulvin (A):
Griseofulvin is a classic systemic antifungal drug used to treat dermatophytosis (ringworm).
It is produced biosynthetically by the fungus Penicillium griseofulvum.
This taxonomic link connects Griseofulvin to the Penicillium-derived group in the list, Penicillin cephalosporin (II).
Thus, A matches with II.
2. Primarily bacteriostatic (B):
Macrolide antibiotics, represented by Erythromycin (I), bind reversibly to the 50S ribosomal subunit of susceptible bacteria.
This inhibits translocation during protein synthesis, preventing bacterial growth and replication without directly killing the cells.
Thus, B matches with I.
3. Primarily bactericidal (C):
Glycopeptide antibiotics, represented by Vancomycin (IV), inhibit cell wall peptidoglycan synthesis by binding to the D-alanyl-D-alanine terminus.
This weakens the bacterial cell wall, leading to osmotic lysis and cell death.
Thus, C matches with IV.
4. Inhibit DNA gyrase (D):
Fluoroquinolone antimicrobials, represented by Ciprofloxacin (III), target bacterial topoisomerase II (DNA gyrase) and topoisomerase IV.
This prevents supercoiling and replication of bacterial DNA, leading to cell death.
Thus, D matches with III.
Combining these matches, we get: A-II, B-I, C-IV, D-III.

Step 3: Final Answer:
The correct matching sequence is A-II, B-I, C-IV, D-III.
Therefore, the correct option is (A).